﻿using System;
using System.Collections.Generic;
using System.Text;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using NPOI.HSSF.UserModel;
using System.IO;
using System.Data;
using System.Windows;
using System.Reflection;
using System.Collections.ObjectModel;

namespace SHKF.B2C.Mannage.AdminUI.View
{
    public class ExcelHelper : IDisposable
    {
        private string fileName = null; //文件名
        private IWorkbook workbook = null;
        private FileStream fs = null;
        private bool disposed;
        public ExcelHelper(string fileName)//构造函数，读入文件名
        {
            this.fileName = fileName;
            disposed = false;
        }

        public Dictionary<string, string> Columns = new Dictionary<string, string>();

        /// 将excel中的数据导入到DataTable中
        /// <param name="sheetName">excel工作薄sheet的名称</param>
        /// <param name="isFirstRowColumn">第一行是否是DataTable的列名</param>
        /// <returns>返回的DataTable</returns>
        public DataTable ExcelToDataTable(string sheetName, bool isFirstRowColumn)
        {
            ISheet sheet = null;
            DataTable data = new DataTable();
            int startRow = 0;
            try
            {
                fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
                workbook = WorkbookFactory.Create(fs);
                if (sheetName != null)
                {
                    sheet = workbook.GetSheet(sheetName);
                    //如果没有找到指定的sheetName对应的sheet，则尝试获取第一个sheet
                    if (sheet == null)
                    {
                        sheet = workbook.GetSheetAt(0);
                    }
                }
                else
                {
                    sheet = workbook.GetSheetAt(0);
                }
                if (sheet != null)
                {
                    IRow firstRow = sheet.GetRow(0);
                    int cellCount = firstRow.LastCellNum; //一行最后一个cell的编号，即总的列数
                    if (isFirstRowColumn)
                    {
                        for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                        {
                            ICell cell = firstRow.GetCell(i);
                            if (cell != null)
                            {
                                string cellValue = cell.StringCellValue;
                                if (cellValue != null)
                                {
                                    string columnName = cellValue;
                                    if (this.Columns.ContainsKey(cellValue))
                                    {
                                        columnName = this.Columns[cellValue];
                                    }

                                    DataColumn column = new DataColumn(columnName);
                                    data.Columns.Add(column);
                                }
                            }
                        }
                        startRow = sheet.FirstRowNum + 1;//得到项标题后
                    }
                    else
                    {
                        startRow = sheet.FirstRowNum;
                    }
                    //最后一列的标号
                    int rowCount = sheet.LastRowNum;
                    for (int i = startRow; i <= rowCount; ++i)
                    {
                        IRow row = sheet.GetRow(i);
                        if (row == null) continue; //没有数据的行默认是null　　　　　　　

                        DataRow dataRow = data.NewRow();
                        for (int j = row.FirstCellNum; j < cellCount; ++j)
                        {
                            if (row.GetCell(j) != null) //同理，没有数据的单元格都默认是null
                                dataRow[j] = row.GetCell(j).ToString();
                        }
                        data.Rows.Add(dataRow);
                    }
                }
                return data;
            }
            catch (Exception ex)//打印错误信息
            {
                MessageBox.Show("Exception: " + ex.Message);
                return null;
            }
        }

        public ObservableCollection<T> ExcelToList<T>(string sheetName, bool isFirstRowColumn) where T:  new()
        {
            ObservableCollection<T> list = new ObservableCollection<T>();

            ISheet sheet = null; 
            int startRow = 0;
            try
            {
                fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
                workbook = WorkbookFactory.Create(fs);
                if (sheetName != null)
                {
                    sheet = workbook.GetSheet(sheetName);
                    //如果没有找到指定的sheetName对应的sheet，则尝试获取第一个sheet
                    if (sheet == null)
                    {
                        sheet = workbook.GetSheetAt(0);
                    }
                }
                else
                {
                    sheet = workbook.GetSheetAt(0);
                }
                if (sheet != null)
                {
                    IRow firstRow = sheet.GetRow(0);
                    int cellCount = firstRow.LastCellNum; //一行最后一个cell的编号，即总的列数
                    List<string> columns = new List<string>();
                  
                    if (isFirstRowColumn)
                    {
                        for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                        {
                            ICell cell = firstRow.GetCell(i);
                            if (cell != null)
                            {
                                string cellValue = cell.StringCellValue;
                                if (cellValue != null)
                                {
                                    string columnName = cellValue;
                                    if (this.Columns.ContainsKey(cellValue))
                                    {
                                        columnName = this.Columns[cellValue]; 
                                    }
                                    columns.Add(columnName);
                                }
                            }
                        }
                        startRow = sheet.FirstRowNum + 1;//得到项标题后
                    }
                    else
                    {
                        startRow = sheet.FirstRowNum;
                    }

                    //最后一列的标号
                    int rowCount = sheet.LastRowNum;
                    Type t = typeof(T);
                    PropertyInfo[] propertys = t.GetProperties();

                    for (int i = startRow; i <= rowCount; ++i)
                    {
                        IRow row = sheet.GetRow(i);
                        if (row == null) continue; //没有数据的行默认是null　　　　　　　

                        T info = new T(); 
                        for (int j = row.FirstCellNum; j < cellCount; ++j)
                        {
                            string value = null; 
                            if (row.GetCell(j) != null) //同理，没有数据的单元格都默认是null
                                value = row.GetCell(j).ToString();

                            string name = columns[j];

                            PropertyInfo propertyInfo = info.GetType().GetProperty(name);

                            if(propertyInfo != null)
                            {
                                if (propertyInfo.PropertyType == typeof(Int64))
                                {
                                    propertyInfo.SetValue(info, long.Parse(value));
                                }
                                else if (propertyInfo.PropertyType == typeof(Int32))
                                {
                                    propertyInfo.SetValue(info, int.Parse(value));
                                }
                                else if (propertyInfo.PropertyType == typeof(Decimal))
                                {
                                    propertyInfo.SetValue(info, decimal.Parse(value));
                                }
                                else if (propertyInfo.PropertyType == typeof(DateTime))
                                {
                                    propertyInfo.SetValue(info, DateTime.Parse(value));
                                }
                                else
                                {
                                    propertyInfo.SetValue(info, value);
                                }
                            } 
                        }

                        list.Add(info);
                    }
                }
               
            }
            catch (Exception ex)//打印错误信息
            {
                MessageBox.Show("Exception: " + ex.Message);
                return null;
            }

            return list;
        }

        //将DataTable数据导入到excel中
        //<param name="data">要导入的数据</param>
        //<param name="sheetName">要导入的excel的sheet的名称</param>
        //<param name="isColumnWritten">DataTable的列名是否要导入</param>
        //<returns>导入数据行数(包含列名那一行)</returns>
        public int DataTableToExcel(DataTable data, string sheetName, bool isColumnWritten)
        {
            int i = 0;
            int j = 0;
            int count = 0;
            ISheet sheet = null;

            fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
            if (fileName.IndexOf(".xlsx") > 0) // 2007版本
                workbook = new XSSFWorkbook();
            else if (fileName.IndexOf(".xls") > 0) // 2003版本
                workbook = new HSSFWorkbook();

            try
            {
                if (workbook != null)
                {
                    sheet = workbook.CreateSheet(sheetName);
                }
                else
                {
                    return -1;
                }

                if (isColumnWritten == true) //写入DataTable的列名
                {
                    IRow row = sheet.CreateRow(0);
                    for (j = 0; j < data.Columns.Count; ++j)
                    {
                        row.CreateCell(j).SetCellValue(data.Columns[j].ColumnName);
                    }
                    count = 1;
                }
                else
                {
                    count = 0;
                }

                for (i = 0; i < data.Rows.Count; ++i)
                {
                    IRow row = sheet.CreateRow(count);
                    for (j = 0; j < data.Columns.Count; ++j)
                    {
                        row.CreateCell(j).SetCellValue(data.Rows[i][j].ToString());
                    }
                    ++count;
                }
                workbook.Write(fs); //写入到excel
                return count;
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception: " + ex.Message);
                return -1;
            }
        }

        public void Dispose()//IDisposable为垃圾回收相关的东西，用来显式释放非托管资源,这部分目前还不是非常了解
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
        protected virtual void Dispose(bool disposing)
        {
            if (!this.disposed)
            {
                if (disposing)
                {
                    if (fs != null)
                        fs.Close();
                }
                fs = null;
                disposed = true;
            }
        }
    }
}
